Near functions should be for frequently used functions that update the game engine are are time critial

far functions are for like menus, file loaders, and such



"
It is also possible to use the small code option, and to override certain functions and pointers to functions as
being
 far.
  However, this method may lead to problems.  The Open Watcom C
16
 compiler generates special
function calls that the programmer doesn’t see, such as checking for stack overflow when a function is
invoked.  These calls are either
 near
 or
 far
 depending entirely on the memory model chosen when the
module is compiled.  If the small code model is being used, all calls will be near calls.  If, however, several
code groups are created with far calls between them, they will all need to access the stack overflow
checking routines.  The linker can only place these special routines in one of the code groups, leaving the
other functions without access to them, causing an error.
To resolve this problem, mixing code models requires that all modules be compiled with the big code
model, overriding certain functions as being near.  In this manner, the stack checking routines can be placed
in any code group, which the other code groups can still access.  Alternatively, a command-line switch may
be used to turn off stack checking, so no stack checking routines get called.
"